JP2018157658A - Electromechanical converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromechanical converter which more strongly generates an electrostatic interaction between a charging part and a stationary electrode by concentrating a line of electric force that is generated from the charging part, to the side of the stationary electrode which faces the charging part.SOLUTION: An electromechanical converter (1) configured to perform conversion between electric power and a motive force by utilizing an electrostatic interaction between a charging part and a stationary electrode that faces the charging part comprises: a stationary substrate (13); a movable member (12) which is movable while keeping a fixed distance to the stationary substrate; multiple stationary electrodes (15 and 16) which are formed on a surface of the stationary substrate facing the movable member while keeping spacing in a movement direction of the movable member; a first charging part (14) which is formed on a surface of the movable member facing the stationary substrate while keeping spacing in the movement direction; and a second charging part (17) which has the same polarity as that of the first charging part, is formed on a surface of the movable member at an opposite side of the opposing surface, and does not face any stationary electrode.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an electromechanical transducer.

  Patent Document 1 includes an electrode to which a sheet-like electret is adhered, and a counter electrode arranged in parallel to the electret sticking surface side of the electrode. The two electrodes are relatively rotated to oppose the electret and the counter electrode. An electrostatic generator is described in which the area is continuously changed and an alternating voltage is generated in a load connected between both electrodes.

  Patent Document 2 describes an electret element that includes an electret film and a charge outflow suppression film that is formed so as to surround the periphery of the side end surface of the electret film and suppresses the charge accumulated in the electret film from flowing out. ing.

  Patent Document 3 describes a mechano-electric energy conversion device in which an electret film is applied to an electret support, and this is opposed to a working electrode, and a charge having the opposite sign to the electret surface charge is induced on the surface. Patent Document 3 describes that the effective charge amount induced on the surface of the working electrode is improved by supporting the electret film as a self-supporting film or by supporting the electret film on an insulating support.

Japanese Patent Laid-Open No. 58-029379 JP 2008-277473 A JP 2009-207344 A

  In an electromechanical converter that performs conversion between electric power and power using an electrostatic interaction between the charging unit and the fixed electrode, the charging unit and the fixed electrode are arranged to face each other. The lines of electric force generated from the charging unit do not necessarily concentrate on the fixed electrode side but diverge around the periphery. The electric lines of force that diverge from the charging unit in directions other than the fixed electrode do not contribute to the electrostatic interaction between the charging unit and the fixed electrode, and thus are wasted.

  In the electret element of Patent Document 2, the outflow of electric charge from the electret film is suppressed by forming a charge outflow suppression film around the side end face of the electret film. This effect is limited to the outer periphery of the electret film. For example, when this charge outflow suppression film is applied to a movable member (rotor) in which charging portions and through-holes are alternately formed radially around the rotation axis, the electric lines of force still remain on the inner peripheral side near the rotation axis. Since the light diverges in a direction other than the fixed electrode, the amount does not contribute to the output of the electromechanical converter and is wasted.

  In addition, in the manufacturing method described in Patent Document 3, the electret film is produced as a self-supporting film, or the electret film is temporarily attached to a metal body during the charging process, and there are many complicated processes, Since it is difficult to handle the electret film, it is difficult to actually manufacture such an electret film.

  The present invention concentrates the electric lines of force generated from a charging unit on the side of the fixed electrode facing the charging unit, and more strongly generates an electrostatic interaction between the charging unit and the fixed electrode. The purpose is to provide a vessel.

  An electromechanical converter that performs conversion between electric power and power using an electrostatic interaction between a charging unit and a fixed electrode facing the charging unit, between the fixed substrate and the fixed substrate A movable member movable at a fixed distance, a plurality of fixed electrodes formed on the surface of the fixed substrate facing the movable member at intervals in the moving direction of the movable member, and the fixed substrate of the movable member Any fixed electrode formed on the opposite surface of the movable member having the same polarity as the first charging portion formed on the opposite surface with a gap in the moving direction, and having the same polarity as the first charging portion. There is also provided an electromechanical converter having a second charging portion that is not opposed to the second charging portion.

  In the above electromechanical converter, the second charging unit is composed of a plurality of partial regions formed at intervals in the moving direction, and the first charging unit and the second charging unit are configured to interpose a movable member. It is preferable that the movable member is formed at the same position in the moving direction on the opposite surface and the opposite surface of the movable member.

  In the electromechanical converter, the movable member is preferably made of a material that can be charged to the same polarity as the first charging unit, and the second charging unit is preferably a base portion of the movable member.

  In the electromechanical converter, the movable member has a plurality of through holes formed at intervals in the moving direction, and the movable member has the first and second charging units and the plurality of through holes in the moving direction. It is preferable that the holes are alternately arranged.

  In the above electromechanical transducer, the movable member is rotatable around a rotation axis passing through the center of the movable member, and the first and second charging units and the plurality of fixed electrodes are radially centered about the rotation axis. It is preferable to arrange | position.

  The electromechanical converter is configured to apply a voltage whose polarity is alternately switched to the plurality of fixed electrodes, and to move the movable member by the electrostatic force generated between the first charging unit and the plurality of fixed electrodes. It is preferable to further have.

  The electromechanical converter preferably further includes a power storage unit that stores electric power generated by electrostatic induction between the first charging unit and the plurality of fixed electrodes in accordance with the movement of the movable member.

  According to the electromechanical transducer described above, the electric lines of force generated from the charging unit are concentrated on the fixed electrode side facing the charging unit, so that the electrostatic interaction between the charging unit and the fixed electrode is further increased. It occurs strongly.

1 is a schematic configuration diagram of an electromechanical converter 1. FIG. 2 is a perspective view of a power generation unit 10. FIG. 2 is a partial cross-sectional view of the power generation unit 10 along a circumferential direction centering on a rotation shaft 11. FIG. It is a figure for demonstrating the charging method of the charging parts 14 and 17. FIG. It is a figure which shows the difference in distribution of the electric force line | wire 80 by the presence or absence of the charging part 17. FIG. It is a figure which shows the difference in the output waveform of the electric power generation part 10 by the presence or absence of the charging part. It is a fragmentary sectional view of electric power generation part 10 'which has another rotating member 12'. It is a figure which shows a general charged column. It is a schematic block diagram of another electromechanical converter 1 '. 6 is a schematic configuration diagram of still another electromechanical converter 2. FIG. 3 is a schematic configuration diagram of still another electromechanical converter 3. FIG. FIG. 3 is a cross-sectional view of the electromechanical converter 1 showing an arrangement example of the rotary weight 18.

  Hereinafter, the electromechanical transducer will be described with reference to the drawings. However, it should be understood that the present invention is not limited to the drawings or the embodiments described below.

  FIG. 1 is a schematic configuration diagram of an electromechanical converter 1. The electromechanical converter 1 includes a power generation unit 10 and a power storage unit 20. The power generation unit 10 includes a rotation shaft 11, a rotation member 12, a fixed substrate 13, charging units 14 and 17 (see FIGS. 2 and 3), and counter electrodes 15 and 16. In FIG. 1, as the power generation unit 10, the upper surface of the fixed substrate 13 and the lower surface of the rotating member 12 are shown side by side. The charging unit 17 is not shown in FIG. 1 because it is disposed on the upper surface of the rotating member 12. The electromechanical converter 1 uses the kinetic energy of the external environment to rotate the rotating member 12 and generates static electricity by electrostatic induction between the charging unit 14 and the counter electrodes 15 and 16, thereby generating electric power from the power. This is a power generation device (electret generator) to be taken out.

  FIG. 2 is a perspective view of the power generation unit 10. FIG. 3 is a partial cross-sectional view of the power generation unit 10 along the circumferential direction around the rotation shaft 11. As shown in FIGS. 2 and 3, the power generation unit 10 includes a rotating member 12 and a fixed substrate 13 that are arranged in parallel to each other. A fixed interval is provided between the rotating member 12 and the fixed substrate 13. In FIG. 3, for the sake of simplicity, the horizontal direction of the drawing is illustrated so as to correspond to the circumferential direction of the rotating member 12 and the fixed substrate 13 (the direction of arrow C in FIG. 2).

  The rotation shaft 11 is an axis that serves as the rotation center of the rotation member 12, and penetrates the center of the rotation member 12 as shown in FIG. 2. The upper and lower ends of the rotating shaft 11 are fixed to a housing of the electromechanical converter 1 (not shown) via bearings. In addition, illustration of the rotating shaft 11 is abbreviate | omitted in FIG.

  The rotating member 12 is an example of a movable member, and is made of a known substrate material such as a silicon substrate or a glass epoxy substrate. As shown in FIG. 2, the rotating member 12 has a disk shape, for example, and is connected to the rotating shaft 11 at the center thereof. The rotating member 12 is formed with a plurality of rectangular or substantially trapezoidal through holes (slits) 121 at equal intervals along the circumferential direction in order to reduce the weight. However, the shape of the illustrated rotating member 12 is an example, and the rotating member may be a flat plate material that does not have a through hole. 3 is a rectangular or substantially trapezoidal portion (hereinafter referred to as a base 122) of the rotating member 12 between the two through holes 121.

  In the electromechanical transducer 1, for example, the rotating member 12 or a rotating weight having a weight balance deviation is attached separately from the rotating member 12. The rotating member 12 is a circumferential direction around the rotating shaft 11 by using the motion of a human body carrying the electromechanical converter 1 or vibration of a machine or the like to which the electromechanical converter 1 is attached as a power source. It can rotate in the direction of arrow C (clockwise and counterclockwise). That is, the rotating member 12 can move with a fixed distance from the fixed substrate 13.

  FIG. 12 is a cross-sectional view of the electromechanical transducer 1 showing an arrangement example of the rotary weight 18. FIG. 12 shows an example in which a rotating weight 18 for rotating the rotating member 12 is arranged separately from the rotating member 12 in the housing of the electromechanical converter 1. In the illustrated example, the rotary weight 18 is attached to a rotary shaft 11 ′ different from the rotary shaft 11 provided in the housing of the electromechanical converter 1. In this case, a gear 19 is attached to the rotary shaft 11, and a gear (speed increasing gear train) 19 'is attached to the rotary shaft 11', and the gear 19 and the gear 19 'are connected. Thereby, the rotary motion of the rotary weight 18 is transmitted to the gear 19 via the gear 19 ', and the rotary member 12 can be rotated.

  The fixed substrate 13 is made of a known substrate material such as a glass epoxy substrate. As shown in FIG. 2, the fixed substrate 13 has a disk shape, for example, and is disposed below the rotating member 12 so as to face the lower surface of the rotating member 12. Unlike the rotating member 12, the fixed substrate 13 is fixed to a housing of the electromechanical converter 1 (not shown).

The charging unit 14 is a thin film made of an electret material, and is formed radially on the lower surface of the rotating member 12 (the surface facing the fixed substrate 13) except for the central portion around the rotating shaft 11. Is formed. The charging unit 14 is an example of a first charging unit, and includes a plurality of rectangular or substantially trapezoidal partial regions formed at intervals in the circumferential direction. The charging units 14 are all charged with the same polarity (for example, negative). Examples of electret materials for the charging unit 14 include resin materials such as CYTOP (registered trademark), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polystyrene (PS), and polytetrafluoroethylene (PTFE). , Polymer materials such as polyvinyldendifluoride (PVDF) or polyvinylfluoride (PVF), or inorganic materials such as silicon oxide (SiO ₂ ) or silicon nitride (SiN) are used.

  The counter electrodes 15 and 16 are each composed of a plurality of rectangular or substantially trapezoidal electrodes, and alternately on the upper surface of the fixed substrate 13 (the surface facing the rotating member 12) in the circumferential direction and centering on the rotating shaft 11 It is formed radially. Each of the counter electrodes 15 and 16 is an example of a plurality of fixed electrodes. The counter electrodes 15 and the counter electrodes 16 are formed at intervals in the circumferential direction and are arranged at equal intervals, like the through-hole 121 and the charging unit 14 of the rotating member 12. On the same circumference around the rotation shaft 11, the widths of the counter electrode 15 and the counter electrode 16 are the same, and the sizes thereof are preferably the same as or substantially the same as the widths of the through hole 121 and the charging unit 14. . In addition, it is preferable that the numbers of the charging unit 14, the counter electrode 15, and the counter electrode 16 are the same.

  The charging unit 17 is a thin film made of an electret material like the charging unit 14, and the upper surface of the rotating member 12 (opposite to the surface facing the fixed substrate 13) except for the central portion around the rotating shaft 11. (Side surface) is formed radially about the rotation axis 11. The charging unit 17 is an example of a second charging unit, and includes a plurality of rectangular or substantially trapezoidal partial regions formed at intervals in the circumferential direction. The charging units 14 and 17 are formed at the same position in the circumferential direction of the rotating member 12 with the base 122 of the rotating member 12 interposed therebetween. For this reason, in the rotating member 12, the charging portions 14 and 17 and the through holes 121 are alternately arranged in the circumferential direction.

  The charging unit 17 is charged to the same polarity as the charging unit 14, and if the charging unit 14 is negative, the charging unit 17 is also all negatively charged. In the electromechanical transducer 1, no fixed electrode is disposed on the upper surface side of the rotating member 12, and the charging unit 17 does not face any fixed electrode. As will be described later, the charging unit 17 is provided on the upper surface side of the rotating member 12 opposite to the fixed substrate 13 to repel electric lines of force that diverge from the charging unit 14 toward the fixed substrate 13. When the rotating member 12 is a flat plate member having no through hole, the charging unit 17 is not divided into a plurality of partial areas and is integrally formed (solid) on the upper surface of the rotating member 12. May be.

  When the rotating member 12 rotates, the overlapping area between the charging unit 14 and the counter electrodes 15 and 16 increases or decreases accordingly. For example, assuming that a negative charge is held in the charging unit 14, the positive charge attracted to the counter electrodes 15 and 16 by the electric field generated by the charging unit 14 increases and decreases as the rotating member 12 rotates. In this way, the power generation unit 10 generates power using electrostatic induction by generating an alternating current between the counter electrode 15 and the counter electrode 16.

  The power storage unit 20 includes a rectifier circuit 21 and a secondary battery 22, and accumulates electric power generated by electrostatic induction between the charging unit 14 and the counter electrodes 15 and 16 according to the rotation of the rotating member 12. Outputs from the counter electrodes 15 and 16 are connected to a rectifier circuit 21, and the rectifier circuit 21 is connected to a secondary battery 22. The rectifier circuit 21 is a bridge-type circuit having four diodes, and rectifies a current generated between the counter electrode 15 and the counter electrode 16. The secondary battery 22 is a chargeable / dischargeable battery such as a lithium secondary battery, accumulates electric power generated by the power generation unit 10, and supplies the electric power to a circuit to be driven (not shown).

  FIG. 4 is a diagram for explaining a charging method of the charging units 14 and 17. When the charging portions 14 and 17 are manufactured, for example, charging electrodes are formed on the upper and lower surfaces of the rotating member 12, and a resin film to be the charging portions 14 and 17 is further formed thereon, as shown in FIG. The rotating member 12 is grounded. Then, the needle electrodes 91 are arranged to face the resin films on the upper and lower surfaces of the rotating member 12, and a high voltage of about several thousand volts is applied to the needle electrodes 91 by the high voltage power supply 90. As a result, electrons are emitted from the needle electrode 91 toward the rotating member 12 by corona discharge, so that the charging portions 14 and 17 on the upper and lower surfaces of the rotating member 12 can be simultaneously negatively charged by the electrons. This charging step may be performed on each side of the rotating member 12.

  FIG. 5A and FIG. 5B are diagrams showing the difference in the distribution of the electric lines of force 80 depending on the presence or absence of the charging unit 17. FIG. 5A shows an enlarged cross section of a portion of one charging unit 14 and the counter electrode 15 in a power generation unit having the same configuration as that of the power generation unit 10 without the charging unit 17. B) shows an enlarged cross section of a portion of one charging unit 14 and the counter electrode 15 in the power generation unit 10.

  When the charging unit 17 is not provided on the upper surface of the rotating member 12, as shown in FIG. 5A, electric lines of force 80 are emitted from the charging unit 14 in the vertical direction. That is, some of the lines of electric force 80 are directed to the lower side of the rotating member 12 where the counter electrode 15 is located, and others are directed to the upper side of the opposite side of the counter electrode 15. The number of lines of electric force generated in the charging unit 14 and the counter electrode 15 is relatively small. The electric lines of force 80 directed to the opposite side of the counter electrode 15 are wasted because they do not contribute to power generation in the electromechanical converter 1.

  On the other hand, when the charging unit 17 is present on the upper surface of the rotating member 12, the electric force lines 80 emitted from the charging unit 14 are the same as the charging unit 14 above the charging unit 14 as shown in FIG. Due to the presence of the polar charging portion 17, it is repelled downward and most of it is directed toward the counter electrode 15. For this reason, in the power generation unit 10, the lines of electric force 80 are concentrated between the charging unit 14 and the counter electrode 15 as compared with the power generation unit 10 without the charging unit 17.

  6A and 6B are diagrams showing the difference in the output waveform of the power generation unit 10 depending on the presence or absence of the charging unit 17. 6A shows an output waveform of the voltage V from the counter electrodes 15 and 16 of the power generation unit having the same configuration as that of the power generation unit 10 except that the charging unit 17 is not provided, and FIG. The output waveform of the voltage V from the counter electrodes 15 and 16 of the part 10 is shown.

  When the charging member 17 is not provided on the upper surface of the rotating member 12, the number of the electric force lines 80 from the charging unit 14 to the counter electrodes 15 and 16 is small, so that an output waveform (AC) is obtained as shown in FIG. (Waveform) amplitude A1 is also small. On the other hand, when the charging unit 17 is on the upper surface of the rotating member 12, more electric lines of force 80 are concentrated between the charging unit 14 and the counter electrodes 15 and 16, as shown in FIG. The electrostatic induction between the charging unit 14 and the counter electrodes 15 and 16 becomes stronger, and the amplitude A2 of the output waveform becomes larger than A1.

  In the electromechanical converter 1 having the power generation unit 10, an electric electrode is formed on the upper surface of the rotating member 12 that is not opposed to the counter electrodes 15 and 16, even though the counter electrode is not disposed on the upper side of the rotating member 12. A charging portion 17 for repelling the force lines is provided. Since the electric force line 80 from the charging unit 14 is directed to the counter electrode 15 side by the charging unit 17 and the electric force line 80 can be concentrated between the charging unit 14 and the counter electrode 15, the electromechanical converter In 1, the amount of power generation increases accordingly. In the electromechanical converter 1, the charging portions 14 and 17 are simply formed on the upper and lower surfaces of the disk-shaped rotating member 12. Therefore, the charging process can be easily performed, the handling of the charging portion is easy, and it is relatively simple. The electric power generation amount of an electret generator can be improved by the method.

  FIG. 7 is a partial cross-sectional view of a power generation unit 10 ′ having another rotating member 12 ′. In FIG. 7, as in FIG. 3, a partial cross section of the power generation unit 10 ′ along the circumferential direction around the rotation shaft 11 is shown. However, also in FIG. 7, illustration of the rotating shaft 11 is omitted. Unlike the rotating member 12, the rotating member 12 ′ is made of a chargeable material for the base 122 itself, and is charged with the same polarity as the charging unit 14. In the electromechanical converter having the power generation unit 10 ′, the base 122 of the rotating member 12 ′ corresponds to the second charging unit. As shown in FIG. 7, in the power generation unit 10 ′, the charging unit 17 of the power generation unit 10 may be omitted, and the upper surface of the rotating member 12 ′ opposite to the counter electrodes 15 and 16 is exposed. If the rotating member 12 ′ itself is made of a material that can be charged, the power generation unit 10 ′ can achieve the effect of improving the power generation amount, similar to the power generation unit 10, even if the charging unit 17 of the power generation unit 10 is omitted. .

  FIG. 8 is a diagram showing a general charge train. Each material listed in the figure is more likely to be negatively charged as the right side in the figure, and more likely to be positively charged as the left side in the figure. When the polarity of the charging unit 14 is negative, the base 122 of the rotating member 12 ′ needs to be negatively charged. Therefore, as the material of the rotating member 12 ′, a material that is negatively charged in the illustrated charging train is used. Among these, what can be processed into the plate material of the substrate may be selected. For example, as the material of the rotating member 12 ′, a fluororesin plate material, Teflon (registered trademark), polyester resin, vinyl chloride, urethane, celluloid, acetate, or the like may be used. Since these materials are insulators, it is not necessary to provide a separate insulating layer at the boundary between the base 122 and the charging unit 14 of the rotating member 12 ′.

  In the power generation unit 10 of the electromechanical converter 1 shown in FIG. 1, the generated current is taken out from the two sets of counter electrodes 15 and 16 formed on the fixed substrate 13. The form of the electromechanical transducer 1 is convenient because it is only necessary to take out current from only the electrodes on the stationary substrate 13 that is stationary, and electrical connection with the rotating member 12 that rotates is unnecessary. However, the present invention is not limited to this configuration, and both the rotating member 12 and the fixed substrate 13 may be electrically connected to the power storage unit 20 to extract the generated current. An example in this case will be described next.

  FIG. 9 is a schematic configuration diagram of another electromechanical transducer 1 ′. The power generation unit 10 ″ of the electromechanical converter 1 ′ has the same configuration as the power generation unit 10 of the electromechanical converter 1 of FIG. 1, but the rotating member 12 is electrically connected to the power storage unit 20. The power generation unit 10 differs from the power generation unit 10 in that only one set of counter electrodes 15 is formed on the fixed substrate 13. In the power generation unit 10 ″, the rotating shaft 11 is made of a conductive member, and each rectangular or substantially trapezoidal partial region that forms the charging unit 14 is connected to the rotating shaft 11 via an electrical contact. In the electromechanical converter 1 ′, the power storage unit 20 is electrically connected to the rotating shaft 11 and the counter electrode 15, and the generated current is taken out through them. Instead of connecting each partial region of the charging film 14 to the rotating shaft 11 one by one, the connecting wires may be connected to the rotating shaft 11 after connecting the partial regions to each other. Alternatively, the rotating member 12 may be formed of a metal material, and each partial region may be directly connected to the rotating shaft 11 via the base of the rotating member 12.

  FIG. 10 is a schematic configuration diagram of still another electromechanical transducer 2. The electromechanical converter 2 includes an actuator 30 and a drive unit 40, and the actuator 30 has the same configuration as that of the power generation unit 10 of the electromechanical converter 1. The counter electrodes 15 and 16 of the electromechanical converter 2 are each connected to the drive unit 40 via electric wiring. The electromechanical converter 2 rotates the rotating member 12 using an electrostatic force generated between the charging unit 14 of the actuator 30 and the counter electrodes 15 and 16 based on the electric signal input to the driving unit 40. This is a drive device (electret motor) that extracts power from electric power.

  The drive unit 40 is a circuit for driving the actuator 30 and includes a clock 41 and comparators 42 and 43. The driving unit 40 applies an alternating voltage whose polarity is alternately switched to the counter electrodes 15 and 16, and rotates the rotating member 12 by electrostatic force generated between the charging unit 14 and the counter electrodes 15 and 16.

  As shown in FIG. 10, the output of the clock 41 is connected to the inputs of the comparators 42 and 43, the output of the comparator 42 is connected to the counter electrode 15, and the output of the comparator 43 is connected to the counter electrode 16 via electric wiring. Connected. The comparators 42 and 43 respectively compare the potential of the input signal from the clock 41 with the ground potential, and output the result as a binary value, but the output signals of the comparators 42 and 43 have opposite signs. When the input signal from the clock 41 is H, the counter electrode 15 has a potential of + V and the counter electrode 16 has a potential of −V. When the input signal is L, the counter electrode 15 has a potential of −V and the counter electrode 16 has a potential of + V. Become.

  When the actuator 30 is driven, the driving unit 40 applies a voltage having the same sign as the charging of the charging unit 14 to one counter electrode 15, and applies a voltage having a sign different from the charging of the charging unit 14 to the other counter electrode 16. Then, the signs of those voltages are alternately inverted. When the voltage is applied in this way, an attractive force or a repulsive force is generated between the charging unit 14 and the counter electrodes 15 and 16 due to the interaction between the electric field generated by the charging unit 14 and the electric field generated by the counter electrodes 15 and 16. . When the drive unit 40 applies an alternating voltage to the counter electrodes 15 and 16, a continuous force is applied to the rotating member 12, so that the rotating member 12 can be rotated.

  Even in the electromechanical transducer 2 having the actuator 30, an electric force is applied to the upper surface of the rotating member 12, which is the side not facing the counter electrodes 15, 16, even though the counter electrode is not disposed on the upper side of the rotating member 12. A charging portion 17 for repelling the wire is provided. Since the electric force lines 80 can be concentrated between the charging unit 14 and the counter electrodes 15 and 16 by the charging unit 17, the electromechanical transducer 2 generates a driving force (rotational torque) correspondingly larger. . In other words, in the electromechanical converter 2, even if the applied voltage is lower than that of the electromechanical converter of the comparative example in which the charging unit 17 is omitted from the actuator 30, the rotation of the same magnitude as the electromechanical converter of the comparative example There is also an effect that torque can be obtained. That is, since the electromechanical converter 2 can be driven with lower power consumption than the electromechanical converter of the comparative example, it is suitable for application to an electronic device such as a wristwatch that is driven by a battery having a small capacity.

  FIG. 11A to FIG. 11C are schematic configuration diagrams of still another electromechanical transducer 3. As shown in FIG. 11A, the electromechanical converter 3 includes an actuator 50 and a drive unit 40. The actuator 50 includes a housing 51, a slide plate 52, a fixed substrate 53, charging units 54 and 57, and counter electrodes 55 and 56. FIG. 11B and FIG. 11C are plan views showing the arrangement of the counter electrodes 55 and 56 and the moving direction of the slide plate 52.

  The electromechanical converter 3 reciprocates the slide plate 52 using the electrostatic force between the charging unit 54 and the counter electrodes 55 and 56 based on the electric signal input to the driving unit 40. A drive device that extracts power from electric power. The movable member of the electromechanical transducer is not limited to the rotating member 12 of the electromechanical transducers 1, 1 ′, 2, but is slidably moved like the slide plate 52 of the electromechanical transducer 3. There may be.

  The slide plate 52 is an example of a movable member, and is made of a known substrate material such as a silicon substrate or a glass epoxy substrate, and is supported in the housing 51 by a movable support portion (not shown). The material of the slide plate 52 may be a conductive metal material such as brass, stainless steel or aluminum. The fixed substrate 53 is disposed on the bottom surface of the box-shaped casing 51. The slide plate 52 can reciprocate in a direction parallel to the fixed substrate 53 (horizontal direction, arrow A direction) while maintaining a certain distance from the fixed substrate 53.

  Similarly to the charging units 14 and 17 of the electromechanical transducers 1, 1 ′ and 2, the charging units 54 and 57 are thin films made of electret materials and are charged with the same polarity (for example, negative). The charging units 54 and 57 are examples of first and second charging units. The charging unit 54 is formed on the lower surface of the slide plate 52, and the charging unit 57 is formed on the upper surface of the slide plate 52, respectively. Each of the charging units 54 and 57 includes a plurality of belt-like (linear) regions extending in a direction orthogonal to the moving direction of the slide plate 52 and arranged at equal intervals in the moving direction of the slide plate 52. In order to reduce the weight of the slide plate 52, through holes (slits) may be formed in the belt-like regions between the charging portions 54 and between the charging portions 57 in the slide plate 52.

  The counter electrodes 55 and 56 are each composed of a plurality of strip-like electrodes extending in a direction orthogonal to the moving direction of the slide plate 52, and are alternately formed on the upper surface of the fixed substrate 53 in the moving direction of the slide plate 52. Each of the counter electrodes 55 and 56 is an example of a plurality of fixed electrodes. It is preferable that the counter electrodes 55 and the counter electrodes 56 are arranged at equal intervals, and the widths thereof are the same. The widths of the counter electrodes 55 and 56 are preferably the same as or substantially the same as the widths of the charging units 54 and 57, and the numbers of the charging unit 14, the counter electrode 55, and the counter electrode 56 are also preferably the same.

  The drive unit 40 is a circuit for driving the actuator 50, and is connected to the counter electrodes 55 and 56 via electric wiring. The drive unit 40 has the same configuration as that of the electromechanical converter 2 and applies a voltage whose polarity is alternately switched to the counter electrodes 55 and 56, so that the drive unit 40 shown in FIGS. As shown, the slide plate 52 is slid in the horizontal direction (arrow A direction) within the housing 51.

  Even in the electromechanical converter 3 having the actuator 50, the slide plate on the side not facing the counter electrodes 55 and 56 even though the counter electrode is not disposed on the upper surface of the casing 51 above the slide plate 52. On the upper surface of 52, a charging portion 57 for repelling the lines of electric force is provided. Since the electric force lines 80 can be concentrated between the charging unit 54 and the counter electrodes 55 and 56 by the charging unit 57, the electromechanical transducer 3 also increases the generated driving force accordingly.

  The drive unit 40 of the electromechanical converter 3 is replaced with the power storage unit 20 of the electromechanical converter 1, and the slide plate 52 is slid in the direction of arrow A using the kinetic energy of the external environment. You may comprise the electric power generating apparatus which produces | generates static electricity by the electrostatic induction between the counter electrodes 55 and 56, and takes out electric power from motive power. Even in the power generation apparatus in this case, the electric force lines 80 can be concentrated between the charging unit 54 and the counter electrodes 55 and 56 by the charging unit 57. Therefore, even in the electromechanical converter 3, the power generation amount is increased accordingly. Become.

1, 1 ', 2, 3 Electromechanical converter 10, 10', 10 '' Power generation unit 11 Rotating shaft 12, 12 'Rotating member 13, 53 Fixed substrate 14, 17, 54, 57 Charging unit 15, 16, 55 , 56 Counter electrode 20 Power storage unit 30, 50 Actuator 40 Drive unit 52 Slide plate

Claims (7)

An electromechanical converter that performs conversion between electric power and power using an electrostatic interaction between a charging unit and a fixed electrode facing the charging unit,
A fixed substrate;
A movable member movable with a fixed distance from the fixed substrate;
A plurality of fixed electrodes formed on the surface of the fixed substrate facing the movable member at intervals in the moving direction of the movable member;
A first charging unit formed on the surface of the movable member facing the fixed substrate at an interval in the moving direction;
A second charging unit having the same polarity as the first charging unit, formed on a surface opposite to the facing surface of the movable member, and not facing any fixed electrode;
An electromechanical converter characterized by comprising: The second charging portion is composed of a plurality of partial regions formed at intervals in the moving direction,
The first charging unit and the second charging unit are respectively formed at the same position in the moving direction on the opposing surface and the opposite surface of the movable member with the movable member interposed therebetween. The electromechanical converter according to claim 1. The movable member is made of a material that can be charged to the same polarity as the first charging unit,
The electromechanical converter according to claim 1, wherein the second charging unit is a base portion of the movable member. The movable member has a plurality of through holes formed at intervals in the moving direction,
The electromechanical conversion according to any one of claims 1 to 3, wherein in the movable member, the first and second charging units and the plurality of through holes are alternately arranged in the moving direction. vessel. The movable member is rotatable about a rotation axis passing through a center of the movable member;
5. The electromechanical converter according to claim 1, wherein the first and second charging units and the plurality of fixed electrodes are arranged radially around the rotation axis.   A drive unit configured to apply a voltage whose polarity is alternately switched to the plurality of fixed electrodes, and to move the movable member by an electrostatic force generated between the first charging unit and the plurality of fixed electrodes; The electromechanical converter as described in any one of Claims 1-5.   6. The power storage unit according to claim 1, further comprising a power storage unit that stores electric power generated by electrostatic induction between the first charging unit and the plurality of fixed electrodes in accordance with the movement of the movable member. The electromechanical converter described in 1.

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